Caulking 101

Someone caulking a window.
What You'll Need
Caulking gun
Utility knife
Caulk remover
Razor scraper
Clean rag
Masking tape

A common bathroom DIY project is caulking. This may be needed in different areas of your bathroom—around the tub, sink, and so on—and it’s actually a simple undertaking that can be easily completed on your own. Here's how to caulk various parts of your bathroom in a few straightforward steps.

What Is Caulking?

Before delving into the tutorial, let’s discuss what caulk actually is along with why it’s useful in bathrooms. Caulk is a waterproof sealant, used most frequently to plug gaps or cracks between building materials. Individuals come into contact with this substance on a day-to-day basis constantly, most of the time probably without even realizing it! Caulking can be painted, and a perk of the application process is that any accidental smears can be cleaned with water. As you’ll read below, caulk application is easy and only requires a few tools.

Choosing the Right Materials and Tools

Caulking a shower or bathtub is easy to do and is a common home DIY project to take on. Before delving into the process, it’s important to buy the right caulk and gun for this project. Because tubs and showers experience frequent moisture, it’s vital to choose a caulk that contains mold and mildew prevention additives. Look for caulk labeled for kitchen and bath use. If this is your first time caulking, look for a latex caulk that fits the bill as it’s easier to apply and clean up. Choosing the right caulk gun makes a difference, too. A high-quality gun, which is still a relatively inexpensive purchase, will go a long way in providing a sturdier plunging mechanism for a smooth and even flow and solid pressure release.

Caulking a Shower, Bathtub, or Bathroom Sink

Someone caulking around a bathroom sink.

Remove Old Caulk

If there is existing caulk around your shower or tub, it needs to be removed before you can add the new caulk. Slice through the substance along the walls with a utility knife to get rid of it. Squirt caulk remover to loosen the caulk and then scrape it off with a razor scraper. Wipe the afflicted area with a dry rag.

Mask the Gaps

Next, it’s important to mask the gaps so you can cleanly apply the caulk. Mask the wall corner gaps first with tape, and then apply tape to the walls above the tub and shower floor.

Cut and Apply

Now, cut the nozzle tip to adequately match the width of the gaps you’re going to be caulking. Hold your gun at a 90-degree angle against the gaps, pushing a bead of caulk slightly ahead of the nozzle while simultaneously pushing the gun forward, applying continuous pressure. Simply fill the gap with caulk—it should not be overflowing.

Shape the Caulk

Wet your finger with water and starting with an outer corner, wipe it across the caulk to remove excess and properly shape it. Do this over every area it was applied to.

Remove the Tape

Remove the masking tape and let the caulk sit for the recommended amount of time (found on the label) before using the shower or tub.

Caulking a Toilet

Next, let’s run through the process to caulk a toilet against the floor. It will be very similar to caulking a tub or shower with a few key differences. Toilets must be caulked to the floor in order to prevent side-to-side movement that could break the toilet’s wax seal. Caulking also prevents splashes and overflows. While it’s tempting to set the toilet and then apply a tiny bead of caulk along the outside edge, that doesn’t always provide a solid bond to the floor. Plus, that method leaves a prominent caulk line, which may not be the desired aesthetic. Learn how to caulk before setting the toilet, below.

Outline the Toilet Placement

Set the toilet in place, sans the wax ring, and square it up to the wall. With masking tape, make an outline of the toilet on the floor. Remove the toilet and turn it on its side, measuring the depth and width of the gluing edge of the bowl.

Caulk the Floor

Someone caulking around a toilet on the floor.

Using your caulk gun, apply caulk directly to the floor, maintaining the inset depth as you follow the tape outline you created.

Install the Wax Ring

Install the wax ring next and then carefully lower the toilet onto the flange.

Firmly Press to Adhere

To ensure that the toilet adheres properly to the caulk, stand on the toilet to apply pressure.

Clean Up

Clean up any excess caulk that oozed out from the sides of the toilet while it's still wet to avoid a dried-on mess.

The caulking process around your bathroom is easy to do and necessary to avoid unwanted leaks and mold growth. Follow these straightforward steps for a seamless bathroom in your home!